Breathing apparatus



8- 1965 D. o. A. JOHANNISSON 3,

BREATHING APPARATUS Filed Nov. 5, 1962 FIG 1 INVENTOR DAG OLOF ALFRED JOHANNlSSON BY $2 1 Q ATTORNEYS United States Patent 3,200,818 BREATHFNG APPARATUS Dag (ilof Alfred lohannisson, Lidingo, Sweden, assignol to Svens'lra Alrtiebolaget Gasaccumnlator, Lidingo, near Stockholm, Sweden, a corporation of Sweden Filed Nov. 5, 1962, Ser. No. 235,566 Claims priority, application Sweden Nov. 17, 1%].

Claims. ((Il. 128-2t)2) The invention relates to a breathing apparatus which may be used for narcosis as well as for artificial respiration and is provided with a supply tube by which a breathing gas or a narcotic can be supplied and with a breathing bag serving as a reservoir of variable volume for storing breathing gas.

In apparatus of this kind it is desirable, should the breathing be arrested for some reason or other, that artificial respiration can be performed by exerting a pressure on the breathing bag for supplying air to the breathing organs. It is further desirable, for instance during an operation, to be able to arrest the respiration by a pressure on the breathing bag without any disturbing effects being produced by the possible continued supply of breathing gas, narcotic or the like by way of the supply tube.

It is further desirable to provide an overflow valve for preventing an increase of pressure in the system beyond a predetermined limit. Such a pressure increase might be caused by a continued supply of breathing gas in larger quantities than are removed from the system, for instance by absorption in a gas purifying device.

The invention overcomes one or more of the disadvantages referred to. It is characterized in that the supply tube is connected to the system to the rear of the breathing bag with regard to the air flow direction and that a non-return valve is provided between the breathing bag and the connection.

FIG. 1 is a view showing the principle of an embodiment of the invention.

FIG. 2 is a view of a detail of FIG. 1.

FIG. 3 is a detail view of a modified apparatus.

The apparatus shown in FIGS. 1 and 2 comprises a valve housing 1 which is adapted to be connected to the breathing organs so as to make possible inhalation and exhalation as indicated by the arrows of the figure. From the valve housing 1 an exhalation tube 2 issues and has connected thereto a supply tube 3. The exhalation tube is connected to a gas purifying device 4, containing a carbonic-acid absorbing agent. From the purifier an inhalation tube 5 is returned to the valve housing. Connected to the tube 5 is a breathing bag 6 serving as a reservoir of breathing gas. A non-return valve 7 is provided in the exhalation tube before its connection to the gas purifier. Just behind the non-return valve, an overflow valve 8 is provided in the exhalation tube. These details are shown on a larger scale in FIG. 2, which shows a disc 9 integral with the upper end of a valve stem lid of the valve 7. The valve member 8 has a central aperture provided therein for the valve .stem ill to be movable in the vertical direction and between the valve stem and the disc 9 there is inserted a spring 11 providing a bias for the non-return valve as well as for the overflow valve.

In the valve housing 1 there is provided a valve disc 12 which in its inoperative position rests on a pair of valve seats, one of which is formed by the end of the exhalation tube 2 and the other of which by the rim of the orifice of the inhalation tube 5.

FIG. 3 shows a detail of a modified apparatus accord ing to FIG. 1, the arrangement shown in FIG. 3 being adapted to be substituted for the portion of the exhalation tube 2 shown in FIG. 1 between the dash-dot lines III of the figure. The arrangement comprises a valve 3,Z,8l8 Patented Aug. 17, 1965 ice piston 13 which is movable between an upper and a lower position. In the upper position the valve housing 1 is connected via the proximate portion of the exhalation tube 2 to the surrounding atmosphere and the portion of the exhalation tube next to the supply tube 3 is blocked. In the lower position, the connection shown in PEG. 1 is established.

The operation is as follows:

On inhalation, a subpressure is set up in the housing 1 and the valve disc 12 is lifted otf its lower valve seat, whereby gas is sucked in from the breathing bag 6.

0n exhalation, the disc 12 is urged by the breathing pressure downwardly to the lower valve seat and the upper valve seat is disengaged, making exhalation possible through the tube 2 and the non-return valve 7 to the gas purifier 4t and on to the breathing bag 6.

The gas supplied from the supply tube 3 passes through the non-return valve 7 to the breathing bag 6. If no counterpressure is present under the non-return valve 7, this valve opens, owing to its larger surface, more easily than the overflow valve 8.

The spring 11 may be adjustable through an adjustment of the disc a For example the disc 9 may be threaded onto the stem 10.

If artificial respiration is to be performed, the breathing bag 6 is compressed so as to make air be supplied to the breathing organs. The non-return valve is then closed and the valve disc 12 is removed from the lower valve seat in the same way as during inhalation.

The breathing may be arrested by the exertion of a certain pressure on the breathing bag 6. The supplied gas can then always flow ofi through the overflow valve 3, owing to the fact that this valve as Well as the supply tube is placed to the rear of the non-return valve with regard to the direction of the air flow.

The common guiding of the non-return valve 7 and the overflow valve 8 with the common spring 11 for biasing both valves has the advantage that the non-return valve 7 in its opened position increases the spring bias on the overflow valve 8, thereby counteracting opening of the latter valve, which would otherwise be possible upon very rapid exhalation.

The modified embodiment according to FIG. 3 operates according to the same principle as just described. However, exhalation now takes place direct to the surrounding atmosphere. The gas purifier 4 may obviously be dispensed with in this case.

What is claimed is:

1. A breathing apparatus comprising: an exhalation tube for conducting exhaled gas from a point of use, an inhalation tube for conducting gas to be inhaled to the point of use, said exhalation tube and said inhalation tube being connected to form a closed circuit leading from and returning to the point of use means in said circuit commuicating with said inhalation and exhalation tubes for permitting one-way flow only from the inhalation tube to the point of use and from the point of use to the exhalation tube, a breathing bag connected in said circuit, .a supply tube connected to said circuit for supplying breathing gas thereto at a point relatively upstream of said breathing bag, a non-return valve in said circuit between said breathing bag and said supply tube opening toward the breathing bag and an overflow valve cornmunicating with said supply tube upstream of said nonreturn valve for discharging excess gas.

2. Apparatus as set forth in claim 1 further comprising means for exerting a relatively increased closing bias on said overflow valve when said non-return valve is open and for exerting a relatively decreased bias on said overflow valve when said non-return valve is closed.

3. Apparatus as set forth in claim 2 wherein said last 3 mentioned means comprises a spring biasing said nonreturn valve and said overflow valve to the closed positions thereof.

4. Apparatus as set forth in claim 1 further comprising means in said circuit for purifying the exhaled gas.

5. Apparatus as set forth in claim 1 wherein the arrangement of said circuit in the downstream direction comprises successively said supply tube, said overflow valve, said non-return valve, and said breathing bag.

6. In a breathing apparatus, a breathing bag, an inhalation tube connected to said breathing bag for conducting breathing gas from the breathing bag to a point of use, means connected to the inhalation tube for preventing reverse flow from the point of use to the inhalation tube, a supply tube communicating with said breathing bag for supplying breathing gas to said breathing bag. a non-return valve between said breathing bag and said supply tube for permitting flow of gas only to said breathing bag from said supply tube, an overflow valve communicating with said supply tube on the side of said non-return valve removed from said breathing bag for 4 discharging excess gas, and means for exerting a relatively strong closing bias on said overflow valve in response to opening movement of said non-return valve and for exerting a relatively lighter closing bias on said overflow valve in response to closing movement of said non-return valve.

References Cited by the Examiner UNITED STATES PATENTS 1,567,868 12/25 Schroder 128-203 2,591,120 4/52 Blease l2829 3,088,456 5/63 Stanton l28-202 FOREIGN PATENTS 928,505 6/55 Germany. 591,654 4/59 Italy.

RICHARD A. GAUDET, Primary Examiner. JORDAN FRANKLIN, Examiner. 

1. A BREATHING APPARATUS COMPRISING: AN EXHALATION TUBE FOR CONDUCTING EXHALED GAS FROM A POINT OF USE, AN INHALATION TUBE FOR CONDUCTING GAS TO BE INHALED TO THE POINT OF USE, SAID EXHALATION TUBE AND SAID INHALATION TUBE BEING CONNECTED TO FORM A CLOSED CIRCUIT LEADING FROM AND RETURNING TO THE POINT OF USE MEANS IN SAID CIRCUIT COMMUNICATING WITH SAID INHALATION AND EXHALATION TUBES FOR PERMITTING ONE-WAY FLOW ONLY FROM THE INHALATION TUBE TO THE POINT OF USE AND FROM THE POINT OF USE TO THE EXHALATION TUBE, A BREATHING BAG CONNECTED IN SAID CIRCUIT, A SUPPLY TUBE CONNECTED TO SAID CIRCUIT FOR SUPPLYING A BREATHING GAS THERETO AT A POINT RELATIVELY UPSTREAM OF SAID BREATHING BAG, A NON-RETURN VALVE IN SAID CIRCUIT BETWEEN SAID BREATHING BAG AND SAID SUPPLY TUBE OPENING TOWARD THE BREATHING BAG AND AN OVERFLOW VALVE COMMUNICATING WITH SAID SUPPLY TUBE UPSTREAM OF SAID NONRETURN VALVE FOR DISCHARGING EXCESS GAS. 